Cholera Toxins. Produced by Vibrio cholerae, cholera toxin (CT) is a multimeric enterotoxin that transfers ADP-ribose to a G protein, locking adenylate cyclase in an 'on' position.
echinoderm. n. 1. (Animals) any of the marine invertebrate animals constituting the phylum Echinodermata, characterized by tube feet, a calcite body-covering (test), and a five-part symmetrical body. The group includes the starfish, sea urchins, and sea cucumbers.ny of various invertebrate sea animals having a hard spiny outer covering, an internal skeleton, and a radially symmetrical body. Starfish, sea urchins, and sea cucumbers are echinoderms.
The adults are recognizable by their (usually five-point) radial symmetry, and include such well-known animals as starfish, sea urchins, sand dollars, and sea cucumbers, as well as the sea lilies or stone lilies. Echinoderms are found at every ocean depth, from the intertidal zone to the abyssal zone.chinoderms have a mesodermal skeleton composed of calcareous plates or ossicles. Each one of these, even the articulating spine of a sea urchin, is composed mineralogically of a crystal of calcite. If solid, these would form a heavy skeleton, so they have a sponge-like porous structure known as stereom.